Chair frame



FIG. 1 is a perspective view of our new design showing the chair frame;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a left-side view thereof, the right-side view being identical;

FIG. 5 is a bottom view thereof; and,

FIG. 6 is a top view thereof.

The ornamental design for a chair frame, as shown and described.